It is likely a fuel system cleaner designed for diesel engines.
Fuel system cleaners are used to clean the fuel system and combustion chamber of an engine, improving fuel efficiency and reducing emissions.
This product may be specifically formulated for use in diesel engines and could help to remove harmful deposits, improve fuel economy, and increase engine performance.
It's important to carefully follow the manufacturer's instructions when using a fuel system cleaner and ensure that the product is compatible with your specific engine and fuel type.